Raw edge belt grinder



Nov. 17, 1959' M. H. KIDD RAW EDGE BELT GRINDER 3 Sheets-Sheet 1 Filed Aprill, 1957 INVENT OR. MfllCOl If. [/00 mwzme/t- 3 Sheets-Sheet 2 Nov. 17, 1959 M. H. KlDD RAW EDGE BELT GRINDER Filed April 1. 1957 Nov. 17, 1959 M. H. KIDD 2,912,797

RAW EDGE BELT GRINDER Filed April 1, 1957 z Sheets-Sheet z Y Maw RAW EDGE BELT GRINDER Malcolm H. Kidd, Dayton, Ohio, assignor toThe Dayton Rubber Company, Dayton, Ohio, a corporation of Ohio Application April 1, 1957, Serial No. 649,681

Claims. (Cl. 51-80) This invention relates to grinding apparatus and more particularly to an improved method and apparatus for grinding and trueing V-belts to substantially eliminate width variation or hop common to die cut V-belts of the prior art. It is particularly advantageous in application to fan belts of the nature used in automotive applications.

V-belt quality control has presented a difficult problem due to the prior lack of an appropriate method and apparatus for trueing the belts. Efforts to grind the belts in a V-block result in dimensional variation and surface irregularities since the belt merely rises in the block as a thick portion is reached. Also, Where attempts are made to grind a single side of a V-belt, the local pressure of the grinding mechanism causes an instability in the belt and a snake-like configuration results.

The subject invention was primarily developed to eliminate these difiiculties attendant the manufacture of raw edge V-belts and improve their dimensional stability. It provides a method and apparatus for trueing V-belts which results in a high quality product of accurate and uniform cross-sectional dimension, The problem of belts riding up and down on pulleys, so prevalent in the use of belts as fabricated in the prior art, is substantially eliminated. The use of the subject invention accordingly insures higher operating etficiency.

The apparatus and method of the invention provide for the simultaneous grinding of both sides of a V-belt with the back or top of the belt which provides its greatest width bearing against means defining a reference plane or surface providing a slight upward component of force to the belt as it is presented to the grinders. While a specific embodiment and application of the invention is presented herein, those versed in the art will readily recognize the invention and its application is not so limited.

A primary object of the invention is to simplify and improve apparatus for and methods of grinding raw edge, die cut V-belts whereby such belts may not only be more economically manufactured, but will be more efiicient and satisfactory in use, adaptable to a greater variety of applications and have a longer operating life with minimum maintenance and replacement requirements.

Another object of the invention is to provide an improved method of grinding V-belts and similar articles to insure dimensional accuracy and uniformity.

A further object of the invention is to provide improved apparatus for grinding V-belts and the like.

An additional object of the invention is to provide a method and apparatus for increasing the quality and the operating efficiency of transmission and drive elements such as raw edge V-belts.

Another object of the invention is to provide apparatus for effecting simultaneous grinding of both sides of a V-belt or the like with the back or top of the belt being held as a reference in a plane slightly higher than its normal line of travel.

States PatentO 2,912,797 Patented Nov. 17, 1959 A further object of the invention is to improve the dimensional uniformity and stability of raw edged V- belts by simultaneously grinding both sides of the belt while maintaining it with its outer surface against a controlling reference plane.

An additional object of the invention is to provide an improved method of trueing V-belts and the like possesssing the advantageous features, the inherent simplicity and deriving improved V-belts as described herein.

A further object of the invention is to provide improvedapparatus for grinding V-belts and the like possessing the advantageous structural features, the inherent meritorious characteristics, and the mode of operation herein described.

With the above primary and other objects in view, as will more fully appear in the specification, the invention intended to be protected by Letters Patent consists of the features of construction, the parts and combinations thereof, and the mode of operation or utilization, as Well as the method practiced, or their equivalents, as hereinafter described or illustrated in the accompanying drawings.

Referring to the drawings wherein is found an illustrative, but obviously not the only form of embodiment of the invention:

Figure 1 is a perspective view of apparatus for grind ing V-belts in accordance with the invention;

Figure 2 is a fragmentary detail .view of the grinding mechanism and the controls therefor as employed in the apparatus of Figure 1;

Figure 3 is a fragmentary enlarged detail view illustrating the relation of the grinding wheels to the V-belt in practicing the invention;

Figure 4 is a fragmentary elevation view of the idler slide and related structure as employed in the apparatus of Figure 1;

Figure 5 is a side view of the apparatus of Figure 4 taken along line 55 thereof;

Figure 6 is a fragmentary detail View of the apparatus provided which provides the reference plane for a belt during the grinding operation; and

Figure 7 is a fragmentary end view taken on line 7-7 of Figure 2, portions of the structure being eliminated to establish clarity of detail.

The invention apparatus and method can be best presented with reference to the embodiment illustrated in the accompanying drawings.

As shown in the drawings, the invention apparatus includes a longitudinally extending main housing section 11 having a drive housing 12 connected at one end and offset in a rearward sense. A motor 13 is mounted within the drive housing 12 to have its drive shaft arranged parallel to a shaft 14 which is rotatably fixed in housing 12 to have one end project outwardly therefrom in vertically spaced relation to the adjacent upper surface of the main housing section 11. Drive pulleys 15 are respectively fixed to the motor drive shaft and the shaft 14 in vertical alignment. A V-belt 16 mounting over the respective pulleys 15 provides a drive from the motor 13 to the shaft 14, a drive pulley 17 being fixed to the outer end of the shaft 14 forwardly of the housing section 12.

The top surface of the main housing'section 11 serves to mount a bed plate 18 which extends from the end of housing section 11 remote from the drive housing to points in spaced relation to the drive housing. The bed plate 18 has longitudinally extending and vertically projecting-side plates 19. A rectangular aperture 20 provided through the upper surface of the housing section 11 intermediate the adjacent extremity of the bed plate 18 and the drive housing substantially defines a grinding station. A rectangular bar element 21 which is pro--.

vided with three spaced apertures is fixed to the bed plate 18 adjacent the aperture 20 in transversely connecting relation to the side plates 19. Also, a similarly apertured bar 22 disposed in transverse connecting relation to the side plates 19 spaced inwardly of the remote end of the bed plate lies parallel to bar 2f with the respective apertures in the bar elements being thus placed in coaxial relation. For purposes of definition, the outermost apertures in the bars 21 and 22 are defined by the numeral 23 in the drawings, while the central apertures are designated by the numeral 24. Guide shafts 25 are mounted to extend between the bars 21 and 22 with their respective ends mounting within the respectively aligned apertures 23 and fixed therein by suitable connecting means such as screws.

An air cylinder 26 is fixed to the bed plate 18 adjacent the remote end of the housing section 11. A shaft 27 connected to a piston within the air cylinder 26 projects axially from the cylinder to extend through the central axially aligned apertures 24 in bearing relation to the bar elements 21 and 22. The shaft 27 is provided with a longitudinally extending fiat 28 at its uppermost surface. It is noted that suitable air controls, not shown, are associated with the air cylinder 26 to provide in the usual manner for longitudinal adjustment of the shaft 27, as required.

A rectangularly formed block is provided which affords an idler slide 29. The slide 29 is longitudinally apertured similarly to the bar elements 21 and 22 to receive the respective shafts 25 and 27 therethrough and mount intermediate the bar elements 21 and 22. The respective outer shafts 25 serve as guide elements for the idler slide 29 which may be adjusted relative thereto and to the shaft 27 to which it may be fixed in any position of adjustment by a lock screw 30 threadedly engaged through the slide 29 to the flat 23 on the shaft. Thus, by suitable controls, movement of the shaft 27 may be effected and the idler slide 29 may be adjusted longitudinally of the guide shafts 25 over the upper surface of the housing section 11.

A reduction unit 31 is mounted on the upper surface of the idler slide to have its input shaft 32 project rearwardly of the housing section ill and beyond the adjacent side plate 19 of the bed plate 18. This adjacent side plate 19 has a bracket plate 33 fixed longitudinally of its outer surface, the upper extremity of which affords a horizontal flange 34- spaced below the projecting input shaft 32. A rack 35 is fixed on the flange 34, coextensive therewith, to have a pinion 36 on the adjacent end of I the input shaft 32 mate in geared relation therewith.

The reduction unit 31 is also provided with an output shaft 36 which projects oppositely relative the input shaft and has a drive pulley 37 fixed to its outer end. A second drive pulley 38, spaced vertically of pulley 37, is fixed to a dial shaft 40 which is disposed parallel to shaft 36' and rotatably mounts in an indicator stand 39, the base of which is fixed to the upper surface of the idler slide 29. A timing belt 41 mounts over the pulleys 37 and 38 to provide a drive of the dial shaft, which has a calibrated dial 42 fixed to its outer extremity forwardly of the indicator stand 39 and facing forwardly to the front of the housing section Ill for purposes to be described. Pointer 44 fixed to the upper extremity of the indicator stand 39 projects forwardly and down to overlie the calibrated face of the indicator dial 42 and serve as a reference pointer.

A pulley support bracket 45 is fixed to project vertically from the upper surface of the idler slide 29 at the end most closely related to the drive housing 12. The bracket 45 is provided at its upper extremity with a horizontally projecting pulley shaft 46 arranged parallel to the pulley shaft 14 projecting from the drive housing. The pulley shaft 46 rotatably mounts a pulley 47 in the plane of the drive pulley 17 on the shaft 14. These pull- 4 eys l7 and 47 serve to mutually reveive a continuous V- belt in the practice of the invention method as Will be further described herein.

As is readily apparent, the block idler slide 29 may be fixedly positioned to the cylinder shaft 27 at any position along its portion capable of lying between the parallel bars 21 and 22 by merely disengaging the lock screw 30 from the cylinder flat 28 and shifting the idler slide to the desired position. By this means, the pulley 47 may be initially disposed in any predetermined space relation to the pulley 11.7 on the shaft 14. And once the V-belt is mounted to the pulleys l7 and 47, a suitable control may be actuated to induce a movement of the cylinder 27 and the connected slide 29 to tension or release the belt as required. It should be noted that the geared relation of the reduction unit on the idler slide to the rack 35 longitudinally disposed relative the housing section 11 will continuously afford a reference by means of the calibrated dial to indicate relative movement of the pulley 47 to the fixed pulley 17.

A fixed channel shaped mounting element St) is connected from front to rear of the housing section ll spaced vertically below the rectangular aperture 2t]! in its upper surface. As shown in the drawings, angle plates 51 fixed to the front and rear inner wall surfaces of the housing setcion l1 serve to support the extremities of the channel mount Sll which are bolted to the angle members by bolts and nuts 52 and 53 respectively. The back of the channel member provides its uppermost surface and its central innermost surface intermediate its depending side plates has an air cylinder 54 bolted thereto and disposed in vetrically depending relation. The air cylinder 54 has its operating shaft 55 projecting vertically through the upper surface of the fixed channel mount to engage in the undersurface of a similar but relatively movable channel mount 56. Aligned bushings 57 and 53 are respectively provided in the movable channel mount 56 and the fixed channel mount 5i? spaced equidistantly from either side of the connecting shaft 55. Guide posts 59 having their upper extremities fixed in respective engagement with the respective bushings 57 in the movable channel mount depend vertically through the fixed channel mount 50 in bearing relation to the axially aligned bushings 58 therein. The guide posts 59 insure that on actuation of the cylinder shaft 55 for vertical displacement of the channel mount 56 relative the fixed channel mount Sll that the displacement will be uniformly parallel.

Screw elements 66 are threadedly connected at their upper ends in bushings 61 in the undersurface of the movable channel mount 56 spaced intermediately of the connected cylinder shaft 55 and the respective depending guide posts 59 to define a common plane therewith. These screws depend vertically through axially aligned bushings 62 in the fixed channel mount to project outwardly and below the channel mount 5%. Threadedly engaged about the screw elements 6t below the fixed channel mount are sprockets 63 which are interconnected by a sprocket chain 64 for conjoint movement. An operating handle 65 connected to one of the sprockets 63 may be rotated to turn the connected sprocket and simultaneously effect a turning of the sprocket on the other screw 60 by means of the sprocket chain 64. In this way the sprockets 53 may be vertically adjusted on the screws 6!) below the fixed channel mount to mutually define means limiting the extent of vertical adjustment of the relatively movable channel mount 56 upwardly of the fixed channel mount.

At the respective extremities of the movable channel mount 56 which lies forwardly and rearwardly of the housing section ill and within the boundaries defined by the rectangular aperture 20 in its upper surfaces are fixed respectively parallel blocks 66, each having a pair of apertures which are respectively axially aligned spaced upwardly of the upper surface of the movable channel mount. The respective pairs of axially aligned apertures in the blocks 66 serve to receive the extremities of a pair of shafts 67, the central portion 68 of each of the shafts being threaded. The shafts 67 are thus disposed parallel and in spaced relation above the movable mount 56. Grinder frames 69 including base portions 70 have a pair of apertured ears 71 in depending relation from said base portions, to receive the parallel shafts 67 therethrough and bear thereon. As arranged, the grinder frames 69 are oppositely disposed in relatively equidistantly spaced relation from the threaded centers of the shafts and adjacent their respective extremities. Nuts 72 are threadedly engaged on the threaded centers of the shafts 67. Depending lugs 73 on the adjacent undersurface portions of the opposite grinder frames 69 are provided with arcuate recesses to bear on the shafts 67 and abut the stop nuts 72 to provide the innermost limit of movement of the grinder frames as will be further described. Pivot mounts 74 are fixed to the respective grinder fnames 69 at identical positions. Air motors 75 mount axially within the respective pivot mounts to project upwardly and outwardly therefrom in identical fashion and mount grinding wheels 76 to their axially projecting drive shafts 77 in identical fashion.

Fixed to the drive housing 12 adjacent the rectangular aperture 20 in the upper surface of the housing section 11 is an arm 78 which projects relatively intermediately of the grinder frames 69 and is provided with a pair of longitudinally spaced apertures 79 disposed vertically. A support and thrust plate 80 having its longitudinal sides adjacent the respective grinder frames angled downwardly and outwardly is mounted to the arm 78 to have its guide shafts 81 depend through the apertures therein. A screw -82 threadedly engaged through the arm 78 intermediately of and in alignment with the apertures therein is arranged to engage the under surface of the support 80 for adjustment of said support plate vertically relative the arm 78 in guided balanced fashion.

The rectangular aperture 20 in the upper surface of the housing section 11, as will be obvious, substantially defines a grinding station in the invention apparatus. The provision for the movable channel mount 56 enables the use of suitable air control for cylinder 54 to be actuated to energize shaft 55 to raise and lower the movable channel mount and thereby the grinder elements 76 to dispose them to opposite sides of the support plate 80 for purposes to be described. The base elements 70 of the respective grinder frames 69 are further connected by an air cylinder 85 respectively connected to one of the base elements and having its projecting shaft 86 connected to the other of the base elements 70 intermediate the depending aperture ears riding on the parallel shafts 67. Again suitable controls are provided for actuation of the air cylinder 85 to enable a balanced and identical movement of the grinder frames 69 towards and away from each other and in bearing relation to the shafts 67. As previously mentioned, the innermost limits for movement of the grinder frames 69 are defined by the stop nuts 72. It is noted that the pivot mounts 74 supporting the motors 75 may be clamped in any selected position of adjustment relative the grinder frames 69 by means of a nut 87 which threadedly engages the pivot element thereof and against the frames 69.

A suggested embodiment of the invention is thus provided. Its use will be defined with respect to its operation in grinding or trueing V-belts. However, it will be readily obvious to those versed in the art that the employment and application of the invention apparatus and modifications thereof is not so limited. Also, the illustration of the invention apparatus will clearly present the improved method of griding or trueing raw edge belts which constitutes an essential part of the subject invention.

In preparation for the belt grinding operation, the support plate 80 must be adjusted by adjustment of the screw 82 to establish its uppermost surface to define a reference plane suitable for the belt section to be trued. Also pulleys 17 and 47 must have groove dimension suitable for the particular application.

Considering the dimension of the continuous V-belt to be trued, the idler slide 29 is adjusted relative cylinder shaft 27 by releasing the lock screw and moving the idler slide on the guide shafts 25 and relative to the shaft 27. The idler slide is then locked to the air cylinder shaft 27 with the air cylinder at the minimum desired travel position, that is minimum relative to the center of the pulley 17 which is essentially fixed. In this Way the center to center distance of the movable pulley 47 with respect to the fixed pulley 1'7 is initially adjusted for the length of the belt to be treated. Since the support 80 constitutes the grinding station, the stop nuts 72 on the shafts 67 must be appropriately adjusted to limit the inward travel of the grinding frames 69 in accordance with the width of the belt to be treated and the pivot mounts 74 must be adjusted to incline the grinding surfaces of the elements '76 to correspond to the inclination of the sides of the V-belt desired. Also, the sprockets 63 must be appropriately adjusted on the screws 60 to insure that the vertical movement of the grinding elements is limited to dispose the grinding elements 76 at their optimum position for the desired results.

By operation of the appropriate air controls for the air cylinder 85 which is of a double acting nature, the

grinding frames 69 are spread apart and then lowered by control through air cylinder 54. The pulley 47 is caused to travel to a preadjusted limit enabled by the fixed positioning of the idler slide to the cylinder shaft 27 and the belt B to be treated is then installed on the two pulleys 17 and 47. Tension is applied to the belt by operation of the cylinder shaft 27 to move idler slide 29 and the pulley 4-7 away from pulley 17. The belt B as disposed on the pulleys is thus established with its top or back of its lower strand bearing against the support which defines the reference plane at the grinding station. The grinding wheels 76 are then raised to their preadjusted limit by control through the air cylinder 54 and its shaft 55 and brought together by actuation through the air cylinder and its shaft 86, connecting to the grinder frames 69, to engage at opposite sides of the belt B where it passes over the reference plane of the support 80. As the energized electric motor 13 drives the pulley 17, the belt B is driven continuously over the support 80. The grinding wheels 76 are driven in a direction opposite to the movement of the belt over the support 80 to simultaneously grind the sides of the belt and contain it to the support 80 in opposition to the thrust provided by the support 80 through the back of the belt in a vertical sense. Thus, the material of the belt is removed by the grinding wheels 76 until the Wheels reach their predetermined limits defined by the stop nuts 72 on the shafts 67 or until the indicator dial on the idler slide 29 clearly indicates that the variation in the belt has been reduced to acceptable limits. It should be noted at this time, that the indicator dial, due to its geared relation to the rack 35, will always transmit the movements of the pulley 47 relative the fixed pulley 17. Thus, means for continual observation of the belt width variation is provided. Of course, as long as there is belt variation, as belt portions of excessive width pass over the movable pulley 47, it and the connected idler slide and shaft 27 of the cylinder 26 will be pulled by the belt toward the fixed pulley 17. This movement will be reflected by the pointer and the indicator dial as previously observed. However, when uniformity of dimen sion is provided in the belts being treated, the relative center to center positions of the pulley 17 and 47 remain substantially constant as will be evident from the indicator dial. This treating operation takes a matter of seconds and another belt may be installed on removal of the belt being treated in the manner described. The cycle may be continuously repeated for each successive belt of 7 the same desired dimension. The specific containment of the belt insures controlled precision grinding.

The invention apparatus and the invention method has been thus described. in the use of the invention center to center variation can be taken out of raw edge belts with machine like precision and speed, and to a degree not previously possible in the prior art. Considerable salvage is enabled by the invention with a consequent savings in time, labor, and material and the precision nature of the belts resulting insures maximum operating efficiency.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advatnage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed comprises an illustrative form of several modes of putting the invention into effect and the invention is therefore claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

Having thus described my invention, I claim:

1. Belt grinding apparatus for trueing or grinding continuous belts including a pair of relatively displaceabie pulleys, one of said pulleys having drive means connected thereto, said pulleys being adjustable in a relative sense to receive and tension a continuous belt, means for applying a thrust perpendicular to a surface of the belt intermediate said pulleys, a pair of grinder elements laterally of said thrust means and pivotally mounted to engage opposite surfaces of the belt and contain it to said thrust applying means, and means for simultaneously energizing said grinder elements to grind said opposite belt surfaces as the belt is driven over said pulleys.

2. The apparatus of claim l including means connected to one of said relatively displaceable pulleys to main tain predetermined tension on the belt being ground and indicator means connected with said last mentioned pulley for indicating dimensional variations in said belt.

3. The apparatus as set forth in claim 1, said means for applying a thrust to said belt being adjustable to displace the portion of the belt which it contacts to a predetermined plane and said grinder elements being operatively connected for simultaneous displacement in both vertical and horizontal sense.

A method of grinding and checking V-belts including the steps of applying a V-belt to a drive means with its back outwardly disposed, driving and applying a predetermined tension to the belt, applying grinder elements to the sides of the belt at a position intermediate the drive and tensioning means and recordin belt tension variation to determine dimensional stability of the belt in the grinding operation.

5. A method of grinding and checking V-helts including the steps of applying a continuous a -belt over a fixed and a relatively movable pulley, drivi and. simultaneously tensioning the belt to an ope. .ag condition to establish the relatively movable pulley at an initial reference position, grinding the sides of the belt and recording the relative movement of said movable pulley during grinding to determine belt width variation and the point of i s correction.

6. V-belt grinding apparatus including pair of relatively displaceable pulleys for mounting a. V-belt to be ground under operating tension, platform means mount ing said pulleys, indicator means connected to one of said pulleys for movement therewith and means opera tively connecting said indicator means to said platform to record movement of said one pulley relative thereto responsive to belt variation acting on said one pulley.

7. Belt grinding apparatus for raw edged V-belts' including, a first support section providing a platform, a second support section mounting a drive means, means mounted for longitudinal displacement on said platform having a pulley element fixed thereto, a fixed pulley connected to said drive means, said pulleys being adapted to mount a V-belt for grinding thereof, means mounted over said platform having a belt support adjustable to engage the back of the belt providing a grinding station, means for engaging the sides of said belt in opposite relation to firmly contain it to said belt support at said grinding station, said side engaging, containing means including grinding elements operative as the belt is driven to effect a uniform dimensional stability to the belt throughout its length, means tensioning said displaceable means during grinding of the belt, a rack fixed longitudinally of said platform, and indicator means on said displaceable means, said indicator means being geared to said rack to record belt variation during the grinding operation.

8. Apparatus for grinding raw edge i -belts including a platform having slide guide means longitudinally of its surface, an idler slide bearing on said slide guide means, means connected to said platform for displacing said idler slide longitudinally of said guide means, a pulley mounted on said idler slide, a drive pulley fixedly positioned relative said platform, said pulley and drive pulley being relatively adiustable by said displacing means to mount an endless V-belt, means in connected relation to said platform below the belt as mounted to said pulleys to define a grinding station intermediate its length, said last named means being vertically adjustable relative said platform, means limiting said vertical adjustment of said vertically adjustable means, bracket elements adjustable transversely of said vertically adjustable means, grinding rneans pivotally mounted to said brackets for disposition at opposite sides or the belt at said grinding station, and means for inclining said grinders to oppositely and simultaneously engage to the belt at the grinding station and efiect a grinding while containing the belt to said adjustable plate.

9. The apparatus of claim 8 including recording means, said displacing means being operable to effect a predetermined tension on the belt being ground, and means operatively connecting said slide guide, said platform and said recording means reflecting belt variation during grinding by recording movement of said displaceable pulley in response to the belt movement over it.

10. Apparatus for grinding a raw edge V-belt comprising means for mounting and advancing said belt in a predetermined path, adjustable means in said path contacting the outer surface of said belt to apply a vertical component of force thereto, a pair of grinder elements above said means oppositely mounted and inclined to engage the opposite beveled surfaces of said belt to oppose said vertical component of force and firmly contain said belt, said grinder element mounting means capable of simultaneous vertical movement, brackets pivotally mounted on said mounting means for angular and vertical adjustment of said grinder elements, and means for energizing said grinder elements to provide uniform dime sional accuracy to the beveled surfaces of said belt.

References (Iited in the file of this patent UNITED STATES PATENTS 

